School of Chemistry and Biochemistry, Georgia Institute of Technology, 901 Atlantic Drive, Atlanta, Georgia 30332-0400, USA.
J Chem Phys. 2011 Mar 7;134(9):094111. doi: 10.1063/1.3556979.
It is commonly argued that the self-interaction error (SIE) inherent in semilocal density functionals is related to the degree of the electronic localization. Yet at the same time there exists a latent ambiguity in the definitions of the terms "localization" and "self-interaction," which ultimately prevents a clear and readily accessible quantification of this relationship. This problem is particularly pressing for organic semiconductor molecules, in which delocalized molecular orbitals typically alternate with localized ones, thus leading to major distortions in the eigenvalue spectra. This paper discusses the relation between localization and SIEs in organic semiconductors in detail. Its findings provide further insights into the SIE in the orbital energies and yield a new perspective on the failure of self-interaction corrections that identify delocalized orbital densities with electrons.
人们普遍认为，半局域密度泛函中固有的自相互作用误差（SIE）与电子局域化程度有关。然而，同时，“局域化”和“自相互作用”这两个术语的定义存在潜在的歧义，这最终阻碍了对这种关系的清晰和易于理解的量化。对于有机半导体分子来说，这个问题尤为紧迫，因为离域分子轨道通常与局域轨道交替出现，从而导致本征值谱的严重扭曲。本文详细讨论了有机半导体中局域化和 SIE 之间的关系。其研究结果进一步深入了解了轨道能量中的 SIE，并为自相互作用校正失败提供了新的视角，该失败将离域轨道密度与电子联系起来。
